Listeners experienced with backness harmony compensate for coarticulation in F2

Abstract

A natural consequence of articulation is the partial assimilation of neighboring vowels in vowel-to-vowel coarticulation (e.g., relative fronting of /ɑ/ in [ɑiCi]). Previous research suggests that listeners are sensitive to coarticulatory variation and perceptually compensate for coarticulation, although the degree of compensation is impacted by how extensive coarticulation is in a language (e.g., English and Shona: Beddor et al., 2002). This study partially replicates Beddor et al. with Turkish listeners (N = 20), who presumably have limited experience with coarticulation in F2 due to pervasive backness harmony in Turkish, on their perception of the Turkish front-back vowel pair /ɛ ɑ/. Participants completed a 4IAX discrimination task with coarticulated /ɛ ɑ/ vowels spliced into appropriate and inappropriate coarticulatory contexts, and vowel identification tasks on an /ɛ-ɑ/ continuum in [bɑb] and [bib] contexts as well as in “no context.” Results suggest that Turkish listeners compensate for coarticulation, supporting the idea that compensation for coarticulation is automatic: Appropriate coarticulation impaired vowel discrimination, and there were boundary shifts in vowel identification across all contexts with significantly different front vowel response proportions (back>no context>front). Moreover, vowels presented with no adjacent coarticulation trigger were perceived more categorically, suggesting that coarticulatory contexts induce more continuous vowel perception.